<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8" />
		<title></title>
		<style type="text/css">
			.box1 {
				width: 300px;
				height: 300px;
				background-color: orange;
				position: relative;
			}

			.box2 {
				width: 100px;
				height: 100px;
				background-color: blue;
				position: absolute;
				top: 0;
				bottom: 0;
				left: 0;
				right: 0;
				margin: auto;
			}
		</style>
	</head>
	<body>
		<div class="box1">
			<div class="box2">
			</div>
		</div>
	</body>
</html>
